Numerous implements include a turnbuckle to adjust height or relative position of structures. Field cultivators and chisel plows, for example, employ several turnbuckles for leveling adjustments. Such agricultural implements as well as industrial equipment and the like are subjected to extremely heavy loading and rugged environmental conditions, and maintaining proper adjustment of the turnbuckle has been problematic. Present locking arrangements include jam nuts, double nuts and special locking washers and nuts which are not always effective or reliable in preventing an eyebolt portion from rotating relative to the turnbuckle. Providing adequate torque on locking nut arrangements is difficult, especially when the turnbuckle adjustments have to be made in the field or at the worksite. When the locking nut works loose, the body of the turnbuckle rotates relative to the eyebolt portion and causes turnbuckle length changes which adversely affect machine adjustments.
Other turnbuckle lock arrangements include flip-over structure for capturing the adjusting nut. However, mounting the flip-over structure has been a problem on round turnbuckles that do not provide a fastening location. In locations having limited space, the turnbuckle lock arrangements can be difficult to mount and operate.
Often, a turnbuckle is designed to fit either side of the assembly to which it is connected, and therefore the locking device must be accessible and operable from both sides. Securing any locking device adequately to resist the heavy forces that can be transmitted through adjusting nut on the turnbuckle continues to be a source of difficulty.